Optical assembly

ABSTRACT

An optical device has a first frame element and second frame element. At least portions of a plurality of optical fiber pairs of an array each including an exposed end are arranged between the two frame elements. A region is defined between opposing surfaces of the two frame elements to hold the optical fibers. When holding the fibers, the two frame elements cooperate to positionally align and orient the exposed ends of each of the optical fibers for at least one of transmitting and receiving light. An optical system with the device includes a TAP photodiode array such that a portion of light is transmitted from at least a pair of input optical fibers to a corresponding pair of photodiodes of the array, and a portion of light is reflected back from an optical filter to output optical fibers corresponding to the input optical fibers.

CROSS-REFERENCE TO RELATED APPLICATION

The present application is a continuation of U.S. patent applicationSer. No. 14/335,014 filed on Jul. 18, 2014, the disclosure of which isincorporated herein by reference.

BACKGROUND OF THE TECHNOLOGY

The present technology relates to optical devices for transmitting andreceiving light through optical fibers and more particularly toalignment and positioning of optical fibers to improve the accuracy ofthe transmission or reception of light through optical fibers.

Optical fibers are often grouped together into assemblies in which thefibers extend generally parallel to each other, i.e., in what are oftentermed “pigtail assemblies,” and terminate within housings that alignone of the ends of the optical fibers. Such assemblies have a variety ofuses, including power monitoring of optical network systems. In oneexample, fibers within one part of a housing are inserted within groovescarved along an axis of the housing such that the fibers are separatedfrom each other. The grooves are formed by two walls defining triangularcross-sections such that the fibers self-align when portions of thefibers contact each of the two walls. The other part of the housing is aflat plate that compresses the optical fibers upon assembly with thegrooved part of the housing. In this configuration, dimensionaltolerances within each of the carved grooves as well as the opticalfibers themselves may accumulate to add to misalignment of the opticalfibers upon assembly of the fibers in the housing.

In another example, a one-piece housing has an aperture that groups endsof optical fibers together into an assembly such that the fibers are incontact with each other. The aperture has four walls that form a squareshape. To form the assembly, the fibers are inserted within the fixedsize of the aperture of the housing such that the dimensional tolerancesof the walls determine the alignment of the fibers as the fibers. Inthis manner, the fibers are either tightly or loosely inserted into thehousing.

In some instances, each of these examples of pigtail assemblies uses oneoptical fiber of an optical fiber pair to transmit light through a lensassembly to a sensor, such as a photodiode. The corresponding opticalfiber of the pair receives a part of the light that is reflected backfrom the lens assembly. The alignment of the fibers in these pigtailassemblies may be sufficient for a single sensor but do not provideadequate alignment of multiple pairs of optical fibers to be used todirect light through a single lens assembly to multiple sensors, such asmay be contained in a photodiode array semiconductor chip.

Therefore, there exists a need for improving the alignment of multiplepairs of optical fibers within an assembly of such fibers.

BRIEF SUMMARY OF THE TECHNOLOGY

In accordance with an embodiment, an optical device may include a firstframe element and may include a second frame element. Each of the firstand the second frame elements may have a surface. When the first and thesecond frame elements are arranged opposing each other, the surfaces ofthe first and the second frame elements may oppose each other, and aregion may be defined by the first and the second frame elements toreceive and hold respective portions of a plurality of pairs of opticalfibers in an array. Each of the portions of the optical fibers may havean exposed end. When the first and second frame elements hold respectiveportions of the plurality of pairs of optical fibers in the array, thefirst and the second frame elements may together cooperate topositionally align and orient the exposed ends of each of the opticalfibers.

In some arrangements, the optical device may include the plurality ofpairs of optical fibers. In some such arrangements, respective portionsof the plurality of pairs of optical fibers may be held in the regiondefined by the first and the second frame elements.

In some arrangements, the exposed ends may be positionally aligned andoriented such that centers of the exposed ends of each of correspondingpairs of the optical fibers may be diametrically opposed about a commoncenter point. In such arrangements, for each of the corresponding pairsof optical fibers, when light is transmitted from the exposed end of onefiber of a corresponding pair to and at least a portion of thetransmitted light is reflected from an at least partially reflectiveobject that may be arranged relative to the optical device, at least aportion of the transmitted light may be received by the other fiber ofthe corresponding pair.

In some arrangements, at least some of the centers of the exposed endsof the optical fibers may be arranged nonlinearly.

In some arrangements, the at least partially reflective object may bearranged to reflect light incident thereon at a same angle at which theincident light is incident on the reflective object along a path otherthan a path along which the incident light travels.

In some arrangements, the exposed ends of pairs of corresponding inputand output optical fibers may define a planar face.

In some arrangements, at least some of the exposed ends of pairs of thenon-corresponding input and output optical fibers may not define aplanar face.

In some arrangements, the first and the second frame elements may eachdefine a groove. The grooves together may form the region when the firstand the second frame elements are arranged opposing each other. Theregion may be configured to hold the portions of the plurality ofoptical fibers arranged in a symmetrical pattern. In some sucharrangements, the groove may have a hemispherical shape when viewed incross-section at an angle parallel to a longitudinal axis of the firstand the second frame elements.

In some arrangements, each of the grooves may be defined by a pluralityof faces. When viewed in cross-section at an angle parallel to alongitudinal axis of the first and the second frame elements, theplurality of faces may define at least an approximately 55 degree anglerelative to each other. In some such arrangements, the region may have ahexagonal shape when viewed in cross-section at an angle parallel to alongitudinal axis of the first and the second frame elements. In othersuch arrangements, the region may have a shape of a parallelogram whenviewed in cross-section at an angle parallel to a longitudinal axis ofthe first and the second frame elements.

In some arrangements, the plurality of faces may be two faces.

In some arrangements, the respective faces of each of the first and thesecond frame elements may form portions of flexible walls. When thefirst and the second frame elements are arranged to oppose each otherand the portions of the fibers are received in the region, the flexiblewalls may contact the portions of the optical fibers between the firstand the second frame elements to hold the portions of the plurality ofoptical fibers arranged in a symmetrical pattern.

In some arrangements, the first frame element, the second frame element,and the plurality of pairs of optical fibers may be held together by anadhesive.

In some arrangements, an optical system may include the optical device.The optical system may include the plurality of pairs of optical fibersand at least one of a pigtail assembly and an optical connector. Thefirst and the second frame elements and the plurality of pairs ofoptical fibers may form a portion of at least one of the pigtailassembly and the optical connector.

In accordance with an embodiment, an optical system for transmitting andreceiving light may include a first frame element and a second frameelement opposing the first frame element. The optical system may furtherinclude an at least partially reflective object and may include an arrayof a plurality of pairs of optical fibers. Each of the optical fibers ofthe array may have at least a portion thereof arranged between the firstand the second frame elements. The first and the second frame elementstogether may cooperate to positionally align and orient exposed ends ofeach of the optical fibers such that centers of the exposed ends of eachof corresponding pairs of the optical fibers are diametrically opposedabout a common center point. In this manner, for each of thecorresponding pairs of optical fibers, when light is transmitted fromthe exposed end of an input fiber of a corresponding pair to the atleast partially reflective object, at least a portion of the transmittedlight is reflected from the at least partially reflective object and isreceived by an output fiber of the corresponding pair.

In some arrangements, the optical system may include a photodiode arrayhaving a plurality of photodiodes for receiving, when light istransmitted from the exposed end of the input fiber of a correspondingpair to the at least partially reflective object, a portion of thetransmitted light that may be passed through and may be furthertransmitted from the at least partially reflective object in a differentdirection than the transmitted light that is reflected by the at leastpartially reflective object. In such arrangements, each of the pluralityof photodiodes may receive transmitted light from a different inputfiber of the plurality of pairs of optical fibers.

In some arrangements, when a second light is received by the outputfiber of the corresponding pair and is transmitted to and passed throughthe at least partially reflective object, the second light passedthrough the at least partially reflective object may be redirected at anangle such that the second light may not be received by the photodiode.

In some arrangements, the optical system may include an element adjacentto the photodiode. The element may be at least one of shaped, oriented,and made of a material to at least one of absorb or redirect the secondlight that is passed through and is further transmitted from the atleast partially reflective object.

In some arrangements, the element may be in the shape of a wedge.

In some arrangements, the element may be shaped and may be oriented toredirect the second light to a location on the optical filter such thatthe optical filter may redirect, to a photodiode of the photodiodearray, the second light that may be redirected from the reflectiveelement.

In some arrangements, the photodiode array may have a surface generallyperpendicular to an axis. In such arrangements, when a second light isreceived by the output fiber of the corresponding pair and istransmitted to and passed through the at least partially reflectiveobject, the axis may be at an angle to the second light passed throughthe at least partially reflective object such that the second light maynot be received by the photo sensors of the photodiode array.

In some arrangements, a first light may be transmitted from an opticalfiber of a first corresponding pair of optical fibers to a first atleast partially reflective object and a second light from an opticalfiber of a second corresponding pair of optical fibers may betransmitted to a second at least partially reflective object. When thefirst light is transmitted from the optical fiber of the firstcorresponding pair of optical fibers to the first at least partiallyreflective object, at least a portion of the first light may bereflected from the first at least partially reflective object and may bereceived by the other fiber of the first corresponding pair of opticalfibers. When the second light from the optical fiber of the secondcorresponding pair of optical fibers is transmitted to a second at leastpartially reflective object, at least a portion of the second light maybe reflected from the second at least partially reflective object andmay be received by the other fiber of the second corresponding pair ofoptical fibers.

In accordance with an embodiment, an optical device for transmittinglight to and receiving light from an at least partially reflectiveobject may include a first frame element and a second frame elementopposing the first frame element. The optical device may further includean array of optical fibers that may include a plurality of correspondingpairs of optical fibers. Each of the optical fibers of the array mayhave at least a portion thereof arranged between the first and thesecond frame elements and may include an exposed end having a center.The first and the second frame elements may cooperate, and in somearrangements together cooperate, to positionally align and orient theexposed ends of each of the optical fibers such that the centers of theexposed ends of each of the corresponding pairs of the optical fibersare diametrically opposed about a common center point. In this manner,for each of the corresponding pairs of optical fibers, when light istransmitted from the exposed end of one fiber of a corresponding pairand at least a portion of the transmitted light is reflected from an atleast partially reflective object, at least a portion of the transmittedlight may be received by the other fiber of the corresponding pair.

In accordance with an embodiment, a method of at least one oftransmitting light to and receiving light from an at least partiallyreflective object may include a step of forming first and second frameelements having surfaces. The surfaces may be adapted to be arranged tooppose each other. The method may include a step of contacting aplurality of pairs of optical fibers between the first and the secondframe elements in which the surfaces of the first and the second frameelements together may cooperate to positionally align and orient exposedends of the optical fibers. The method may further include a step of atleast one of transmitting light from, receiving light at, andtransmitting light from and receiving light at the exposed end of eachof the plurality of optical fibers.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a schematic of an optical system in accordance with anexample of the present technology, in which details of frame elements ofa housing within the optical system have been excluded for illustrationpurposes.

FIG. 2 shows a schematic of an optical system in accordance with anexample of the present technology, in which details of frame elements ofa housing within the optical system have been excluded for illustrationpurposes.

FIGS. 3A and 3B show detailed perspective views of respective endportions of an optical assembly of the optical system of FIG. 1.

FIG. 4 shows a perspective view of a portion of a covered end of anoptical assembly in accordance with an example of the presenttechnology.

FIG. 5 shows a perspective view of a portion of a covered end of anoptical assembly in accordance with an example of the presenttechnology.

FIG. 6 shows a perspective view of a portion of a covered end of anoptical assembly in accordance with an example of the presenttechnology.

FIGS. 7A and 7B show schematics of an optical system in accordance withan example of the present technology, before and after the addition of aredirection element, respectively, when a second optical input istransmitted from an output optical fiber.

DETAILED DESCRIPTION

Referring now to the drawings, optical system 10 shown in FIG. 1 andoptical system 10A shown in FIG. 2 may include optical assemblies 100and 100A, respectively. Optical assemblies 100 and 100A may include acollection of a plurality of pairs of input and output optical fibers101, 102 that may be held together, fixed in position, and at leastpartially covered by housings 110 and 110A, respectively. The opticalfibers 101, 102 may be but are not limited to being glass fibers. Theplurality of pairs of input and output optical fibers 101, 102 may bearranged such that ends 103, 104 of input and output optical fibers 101,102, respectively, that are covered by housings 110, 110A may definerectangular shapes in 2×N and 1×N configurations.

System 100 may further include lens assembly 120. Lens assembly 120 mayinclude optical filter 130 that may be placed between and in contactwith lenses 140, 145. As shown, optical filter 130 and each of lens 140,145 may be but are not limited to being cylindrically shaped and mayhave but are not limited to having the same or substantially similaroutside diameters. In some arrangements, lens assembly 120 may furtherinclude a shell (not shown), which may be but is not limited to beingcylindrical, in which optical filter 130 and each of lenses 140, 145 maybe at least partially contained and fixed in relative positions to eachother.

As in the example shown, optical filter 130 may be a partiallytransmitting and partially reflecting optical filter, commonly known asa TAP filter. In some arrangements, optical filter 130, which may be butis not limited to any of being made of glass, being made of plasticssuch as polycarbonates or acrylics, or more preferably being amultilayered thin film coating made of dielectric materials, such asSiO₂ and TiO₂.

As further shown, system 100 may further include a plurality of sensors150 for detecting light waves or signals originating from the pluralityof optical fibers 101, 102. Sensors 150 may be photodiodes which may bearranged as a photodiode (PD) array of a semiconductor chip 160. Basedon the signals received by the PD array of the chip 160, correspondinginstructions may be initialized and transmitted by operation of aprocessor or circuitry (not shown) included in the chip 160.

These instructions may be but are not limited to being used to monitorthe existence of a signal. When used in this manner, a substantialportion of light transmitted from input fiber 101 may be received bycorresponding output fiber 102 and only a small portion of light may bereceived by sensors 150. In some arrangements, approximately 99% of thelight transmitted by an input fiber may be received by a correspondingoutput fiber and the remaining approximately 1% of light transmittedfrom the input fiber may be received by one or more associated sensors,such as photodiodes on one or more PD array chips. It is to beunderstood that any ratio of light transmitted from an input fiber andreceived by a corresponding output fiber and by one or more associatedsensors is contemplated within the scope of the technology.

As shown in the detailed views of optical assembly 100 in FIGS. 3A and3B, each of the plurality of pairs of input and output optical fibers101, 102 may be encapsulated on an end 105, 106, respectively, oppositeof respective covered ends 103, 104, by encapsulant 107. Encapsulant 107may be a coating which may be but is not limited to being made ofacrylic. Encapsulant 107 may cover only a respective portion of opticalfibers 101, 102 such that another respective portion of optical fibers101, 102 between covered ends 103, 104 and encapsulant 107 may beexposed. The portions not covered by encapsulant 107 may be exposed bystripping the encapsulant 107 from optical fibers 101, 102.

As further shown in the arrangement of FIGS. 3A and 3B, housing 110 mayinclude first and second frame elements 111, 112 that may surround andhold, desirably fixed in position, the plurality of pairs of input andoutput optical fibers 101, 102. Each of first and second frame elements111, 112 may include first and second walls 113, 114 along a length ofthe first and second frame elements 111, 112. First and second walls113, 114 may be perpendicular or substantially perpendicular to eachother, i.e., may form an angle preferably in the range betweenapproximately 550° and 125°, and more preferably in the range betweenapproximately 60° and 120°. First and second walls 113, 114 also may bein the range between approximately 80° and 100°, and further may be inthe range between approximately 85° and 95°. In this manner, whenassembled, first and second frame elements 111, 112 may interface at andalong wall 113 of one of frame elements 111, 112 and interfacing thirdwall 115 of the other frame elements 111, 112. In this manner, frameelements 111, 112 of housing 110 may cooperate to define an inner regionin which the pairs of input and output optical fibers 101, 102 may beheld together, fixed in position, to form the 2×N configuration ofoptical fibers 101, 102, as described previously herein with respect toFIG. 1.

In the 2×N assembled configuration shown in FIGS. 1, 3A, 3B, coveredends 103, 104 of the pairs of input and output optical fibers 101, 102may define two rows of adjacent and contacting parallel optical fibersthat may extend along the length of and may terminate at one end 118 ofhousing 110. In this configuration, the perpendicularity of walls 113,114 of each of frame elements 111, 112 may form an L-shape in whichwalls 113 of each of frame elements 111, 112 may be oriented to faceeach other and may be parallel to interfacing third wall 115. In thismanner, each covered end 103 in the row of covered ends 103 may extendalong wall 113 of frame element 111 and each covered end 104 in the rowof covered ends 104 may extend along wall 113 of frame element 112 inwhich all of the optical fibers of the rows of covered ends 103, 104 maybe parallel to each other. Additionally, outermost covered ends ofoptical fibers from each row of the plurality of optical fibers 101, 102may extend along wall 114 of frame element 111, and opposing outermostcovered ends of optical fibers from each row of the plurality of opticalfibers 101, 102 may extend along wall 114 of frame element 112.

Each covered end 103, 104 of optical fibers 101, 102 may includerespective input and output tips 108, 109 that may be exposed at end 118of housing 110. In this manner, input optical fibers 101 may transmitlight or other input optical signal that may pass through fibers 101 ina direction away from fibers 101, and output optical fibers 102 mayreceive light or other output or feedback optical signal that then maybe passed through optical fibers 102. As best shown in FIGS. 3A and 3B,the exposed input and output tips 108, 109 may all lie in the same planeto define a planar face of the optical fibers. Further, the exposedinput and output tips 108, 109 and the frame elements 111, 112 of thehousing 110 may all lie in the same plane to define a planar face of theoptical assembly 100.

In accordance with the technology, when optical fibers 101, 102 areassembled within housing 110, first and second frame elements 111, 112may contact the plurality of optical fibers 101, 102, optionallycompressing the optical fibers 101, 102, such that optical fibers 101,102 are held fixed in relative alignment with each other. In thismanner, at least two corresponding pairs of input and output opticalfibers 101, 102 (the correspondence between pairs being designated bythe dashed lines shown in FIG. 3B) may define a same center point 199that is equidistant from and collinear with fiber centers 99 of each ofinput and output tips 108, 109 of each of the corresponding pairs ofoptical fibers 101, 102.

In particular, in the example of FIGS. 3A and 3B, due to theconstruction and assembly of frame elements 111, 112 around covered ends103, 104 of the plurality of pairs of input and output optical fibers101, 102, tips 108 and 109 of each of the input and output opticalfibers 101, 102 may be aligned and may be oriented such that center 199may be between input optical fiber 101A and output optical fiber 102Aand also between input optical fiber 101B and output optical fiber 102B.

In this manner and referring again to FIG. 1, when optical assembly 100of optical system 10 is arranged to receive optical inputs 20, which asshown may be light waves (represented by arrows pointing away fromoptical input fibers 101) transmitted from input tips 108 of inputoptical fibers 101A and 101B, a portion 24 of each of transmittedoptical inputs 20 may pass through and may be transmitted by opticalfilter 130, and a portion 26 of each of transmitted optical inputs 20may be reflected from optical filter 130 and may be received by outputoptical fibers 102A and 102B, respectively. Similarly, when opticalinputs 20 are transmitted from the other input optical fibers 101 ofoptical assembly 100, portions 24 of the transmitted optical inputs 20may pass through and may be transmitted by the optical filter 130, andportions 26 of the transmitted optical inputs 20 may be reflected fromthe optical filter 130 and may be received by the output optical fibers102 corresponding to the respective input optical fibers 101.

FIG. 4 shows a variation of the example of FIG. 3. In this example,optical assembly 200 is substantially similar to optical assembly 100described previously herein with respect to FIG. 3 with the exceptionthat frame elements 211, 212 of housing 210 may have inner walls 213,214 that may not be perpendicular to each other and instead may formoblique angles with each other. As shown, frame elements 211, 212 may beidentical to each other for ease of manufacturing. In this manner andsimilar to the example of FIG. 3, frame elements 211, 212 may interfaceand cooperate with each other to align ends of corresponding pairs ofinput and output optical fibers inserted in the frame elements such thateach of the corresponding pairs of input and output optical fibers havea shared center 299 defined between a center of a tip of eachcorresponding input and output optical fibers. In this manner, whenoptical assembly 200 is used in conjunction with an optical system suchas optical system 10 and optical inputs such as light are transmittedfrom the input optical fibers of optical assembly 200, a portion of theoptical inputs may be transmitted by an optical filter within theoptical system and a portion of the optical inputs may be reflected fromthe optical filter to corresponding output optical fibers 102 of theassembly 200.

FIG. 5 shows another variation of the examples of FIGS. 3 and 4. In thisexample, optical assembly 300 is substantially similar to opticalassembly 100 with the exception that walls 313, 314 may form obliqueangles with mating walls 316, 317 of frame elements 311, 312 of housing310 of the assembly 300. Similarly to the examples of FIGS. 3 and 4, inthis example, corresponding pairs of input and output optical fibers maybe held together, fixed in position, upon insertion within and assemblyof frame elements 311, 312 such that centers of tips of covered ends ofthe input and output optical fibers may have a shared center 399 definedbetween the centers of corresponding input and output optical fibers. Inthis manner, when optical assembly 300 is used in conjunction with anoptical system such as optical system 10 and optical inputs such aslight are transmitted from the input optical fibers of optical assembly300, a portion of the optical inputs may be transmitted by an opticalfilter within the optical system and a portion of the optical inputs maybe reflected from the optical filter to corresponding output opticalfibers of the assembly 300.

Referring now to FIG. 6, optical assembly 400 may be substantiallysimilar to optical assembly 300 as shown in FIG. 5 with the exceptionthat housing 410 of optical assembly 400 may include frame elements 411,412 that each may include additional wall 419 between walls 413, 414. Inthis configuration, walls 413, 414 may form an oblique angle with matingsurfaces 416, 417 of the respective frame elements 411, 412 andadditional walls 419 of each of frame elements 411, 412 may be parallelto mating surfaces 416, 417 and thus parallel to each other. In thismanner and similar to the example of FIG. 5, frame elements 411, 412 mayinterface and cooperate with each other to align ends of correspondingpairs of input and output optical fibers inserted in the frame elementssuch that each of the corresponding pairs of input and output opticalfibers have a shared center 499 defined between a center of a tip ofeach corresponding input and output optical fibers. In this manner, whenoptical assembly 400 is used in conjunction with an optical system suchas optical system 10 and optical inputs such as light are transmittedfrom the input optical fibers of optical assembly 400, a portion of theoptical inputs may be transmitted by an optical filter within theoptical system and a portion of the optical inputs may be reflected fromthe optical filter to corresponding output optical fibers of theassembly 400.

As shown in FIG. 7A, an additional optical input 550, such as light orlight waves or signals, which may be unwanted, may be transmitted, insome instances undesirably, to and pass through output optical fiber 502of an optical system 500 that may be substantially similar to opticalsystem 100, towards an optical filter (not shown) of a lens assembly 520and PD array chip 560, which may be substantially similar to opticalfilter 130 and PD array chip 160 as described with respect to FIG. 1. Insuch instances, the optical filter may transmit a portion 555 ofadditional optical input 550 from a first location on the optical filtertoward header surface 570 that may be adjacent to the PD array chip 560.The portion 555 of additional optical input 550 then may be reflectedback from header surface 570 to a second location of the optical filterdifferent from the first location from which the portion 555 was firsttransmitted by the optical filter. The portion 555 of additional opticalinput 550 further may be reflected from the second location of theoptical filter to PD array chip 560, and, in some instances to a firstphotodiode 561 on PD array chip 560 to which an optical input istransmitted from the optical filter which originates from the firstinput optical fiber corresponding to the first output optical fiberthrough which the additional optical input 550 originates. Theimpinging, i.e., striking, of the multiple optical inputs to the samephotodiode, such as photodiode 561, may be undesirable, becauseinformation indicated by a desired one of the optical inputs may not bedetectable at the photodiode, such that erroneous instructions, or othertype of information or output from the photodiode, may be generated atthe PD array chip 560 from such detection.

As shown in FIG. 7B, element 575 may be positioned adjacent to PD arraychip 560 of optical system 500 and configured and oriented to at leastone of absorb and redirect portion 555 of additional optical input 550when portion 555 is transmitted from the first location on the opticalfilter of lens assembly 520. Element 575 may be but is not limited tobeing in the shape of a wedge, and may have but is not limited to havingat least one of a reflective and absorptive surface, such as may beformed by a metallic coating. In this manner, additional optical input550 may be at least one of absorbed and redirected away from the opticalfilter and thus prevented from being redirected to PD array chip 560.

Although not shown in any drawings, in an example of a variation ofoptical system 500, element 575 may be configured and oriented such thatthe portion of additional optical input 550 impinging element 575 may beat least one of actively and intentionally redirected from the opticalfilter to a desired photodiode of the PD array. Such a configuration maybe used for detection of unwanted optical input, such an unwanted lightor may be used for other failure diagnostic purposes.

Although also not shown in any drawings, in an example of anothervariation of optical system 500, header surface 570 and thus PD array560 attached to header surface 570 may be at least one of rotated,articulated, oriented and otherwise positioned in a manner such thatportion 555 of additional optical input 550, which may be an unwantedoptical input, may not be redirected to a photodiode of PD array 560. Insuch a configuration, a portion of additional optical input 550 that maybe reflected from header surface 570 may be redirected such that theportion of the additional optical input is not directed towards theoptical filter. In some such arrangements, an additional element otherthan the PD array 560 that may provide for at least one of redirectionand absorption may not be used.

In the examples shown and described previously herein, each of the firstand second frame elements of the optical assembly has been shown asbeing identical or substantially identical such that they areinterchangeable. However, in alternative arrangements in accordance withthe technology described herein, first and second frame elements mayhave at least one of a different size dimension and a different shape.

In accordance with the technology, each of the first and second frameelements may be hollow, although in other arrangements, first and secondframe elements used to hold optical fibers in the same manner may besolid or at least substantially solid.

In some alternative arrangements of the technology, includingarrangements similar to that shown in the example of FIGS. 1, 3A, and 3Bin which there are two parallel rows of covered ends of pairs of opticalfibers, the input and optical fibers could be arranged in various ways,including having the input and output fibers in the same row as well ashaving all of the input fibers on one end (e.g., near one of the walls114) and all of the output fibers on the opposite end (e.g., near theother of the walls 114), so long as the fiber centers of the tips ofmultiple corresponding pairs of input and output optical fibers arediametrically opposed about a common center point.

In some alternative arrangements, a plurality of optical filters, suchas optical filter 130, may be used in conjunction with a plurality ofpairs of corresponding input and output optical fibers. In some suchconfigurations in accordance with the technology, a plurality of suchpairs of corresponding input and output optical fibers may be associatedwith one optical filter while another plurality of such pairs ofcorresponding input and output optical fibers may be associated withanother of the plurality of optical filters in the manner describedpreviously herein. In arrangements having a plurality of opticalfilters, the optical filters may be but are not limited to beingattached by way of a shell of a lens assembly or may be separated fromeach other.

In some arrangements of the technology, centers of the exposed tips atthe covered ends of the optical fibers may be arranged linearly, such asin a 1×N configuration as previously described herein, or may bearranged nonlinearly, such as in (1+N)×N including a 2×N configurationas previously described herein. In some alternative arrangements,centers of the exposed ends of corresponding pairs of the input andoutput optical fibers may lie in a different plane than centers of theexposed ends of a different corresponding pair of the input and outputoptical fibers. In this manner, the plurality of input and output fibersmay not define a planar face.

In some arrangements of the technology, sensors, such as the sensors 150discussed previously herein, which may be photodiodes, may be arrangedon aligned multiple PD array chips in which each of the multiple chipshas one PD active area.

It is to be understood that the disclosure set forth herein includes allpossible combinations of the particular features set forth above,whether specifically disclosed herein or not. For example, where aparticular feature is disclosed in the context of a particular aspect,arrangement, configuration, or embodiment, that feature can also beused, to the extent possible, in combination with and/or in the contextof other particular aspects, arrangements, configurations, andembodiments of the technology, and in the technology generally.

Furthermore, although the technology disclosed herein has been describedwith reference to particular features, it is to be understood that thesefeatures are merely illustrative of the principles and applications ofthe present technology. It is therefore to be understood that numerousmodifications, including changes in the sizes of the various featuresdescribed herein, may be made to the illustrative embodiments and thatother arrangements may be devised without departing from the spirit andscope of the present technology. In this regard, the present technologyencompasses numerous additional features in addition to those specificfeatures set forth in the claims below. Moreover, the foregoingdisclosure should be taken by way of illustration rather than by way oflimitation as the present technology is defined by the claims set forthbelow.

The invention claimed is:
 1. An optical device comprising: a pluralityof pairs of optical fibers held together within a defined region,wherein respective portions of the plurality of pairs of optical fibersare arranged in an array, each of the portions having an exposed endoriented such that centers of the exposed ends of each of correspondingpairs of the optical fibers are diametrically opposed about a commoncenter point and such that, for each of the corresponding pairs ofoptical fibers, when light is transmitted from the exposed end of onefiber of a corresponding pair and at least a portion of the transmittedlight is reflected from an optical filter arranged relative to theoptical device, at least a portion of the transmitted light is receivedby the other fiber of the corresponding pair.
 2. The optical device ofclaim 1, wherein at least some of the centers of the exposed ends of theoptical fibers are arranged nonlinearly.
 3. The optical device of claim1, wherein the optical filter is arranged to reflect light incidentthereon at a same angle at which the incident light is incident on thereflective object along a path other than a path along which theincident light travels.
 4. The optical device of claim 1, wherein theexposed ends of pairs of corresponding input and output optical fibersdefine a planar face.
 5. The optical device of claim 1, wherein at leastsome of the exposed ends of pairs of the non-corresponding input andoutput optical fibers do not define a planar face.
 6. The optical deviceof claim 1, wherein the centers of the exposed ends of the opticalfibers are arranged in a symmetrical pattern.
 7. An optical assembly,comprising: the optical device of claim 1, wherein the optical assemblyincludes the plurality of pairs of optical fibers and at least one of apigtail assembly and an optical connector, and wherein the plurality ofpairs of optical fibers form a portion of the at least one of thepigtail and the optical connector.
 8. An optical system comprising: theoptical device of claim 1; and a lens through which at least a portionof the light is transmitted from the exposed end of the one fiber of thecorresponding pair of the optical fibers to the optical filter.
 9. Anoptical system comprising: the optical device of claim 1; and a lensassembly comprising a pair of lenses and an optical filter between thepair of lenses through which at least a portion of the light istransmitted, the positions of the pair of lenses and the optical filterbeing fixed relative to the optical device.
 10. The optical system ofclaim 9, further comprising a plurality of sensors for detecting atleast some of the portion of the light transmitted through the pair oflenses.
 11. An optical system for transmitting and receiving light,comprising: an at least partially reflective object; and an array of aplurality of pairs of optical fibers held together, each of the opticalfibers of the array having at least a portion thereof positionallyaligned and oriented such that centers of exposed ends of the portionsof each of corresponding pairs of the optical fibers are diametricallyopposed about a common center point and such that, for each of thecorresponding pairs of optical fibers, when light is transmitted fromthe exposed end of an input fiber of a corresponding pair to the atleast partially reflective object, at least a portion of the transmittedlight is reflected from the at least partially reflective object and isreceived by an output fiber of the corresponding pair.
 12. The opticalsystem of claim 11, further comprising a photodiode array having aplurality of photodiodes for receiving, when light is transmitted fromthe exposed end of the input fiber of a corresponding pair to the atleast partially reflective object, a portion of the transmitted lightthat is passed through and is further transmitted from the at leastpartially reflective object in a different direction than the portion ofthe transmitted light that is reflected by the at least partiallyreflective object, each of the plurality of photodiodes receiving theportion of the transmitted light from a different input fiber of theplurality of pairs of optical fibers.
 13. The optical system of claim12, wherein, when a second light is received by the output fiber of thecorresponding pair and is transmitted to and passed through the at leastpartially reflective object, the second light passed through the atleast partially reflective object is redirected at an angle such thatthe second light is not received by the photodiode receiving the portionof the transmitted light from the respective corresponding pair of theoptical fibers.
 14. The optical system of claim 13, further comprising:an element adjacent to the photodiode array, the element being at leastone of made of a material, shaped, and oriented to at least one ofabsorb or redirect the second light that is passed through and isfurther transmitted from the at least partially reflective object. 15.The optical system of claim 14, wherein the element is in the shape of awedge.
 16. The optical system of claim 14, wherein the element is shapedand oriented to redirect the second light to a location on an opticalfilter such that the optical filter redirects the second lightredirected from the element to a photodiode of the photodiode array. 17.The optical system of claim 12, wherein the photodiode array has asurface generally perpendicular to an axis, wherein when a second lightis received by the output fiber of the corresponding pair and istransmitted to and passed through the at least partially reflectiveobject, the axis is at an angle to the second light passed through theat least partially reflective object such that the second light is notreceived by photo sensors of the photodiode array.
 18. The opticalsystem of claim 11, wherein, when a first light is transmitted from anoptical fiber of a first corresponding pair of optical fibers to a firstlocation of the at least partially reflective object, at least a portionof the first light is reflected from the first location of the at leastpartially reflective object and is received by the other fiber of thefirst corresponding pair of optical fibers, and wherein, when a secondlight from an optical fiber of a second corresponding pair of opticalfibers is transmitted to a second location of the at least partiallyreflective object, at least a portion of the second light is reflectedfrom the second location of the at least partially reflective object andis received by the other fiber of the second corresponding pair ofoptical fibers.
 19. An optical device for transmitting light to andreceiving light from an at least partially reflective object, theoptical device comprising: an array of optical fibers including aplurality of corresponding pairs of optical fibers held together, eachof the optical fibers of the array including an exposed end having acenter, wherein centers of the exposed ends of each of the correspondingpairs of the optical fibers are diametrically opposed about a commoncenter point such that, for each of the corresponding pairs of opticalfibers, when light is transmitted from the exposed end of one fiber of acorresponding pair and at least a portion of the transmitted light isreflected from an at least partially reflective object, at least aportion of the transmitted light is received by the other fiber of thecorresponding pair.
 20. An optical system comprising: the optical deviceof claim 19; and a plurality of sensors for receiving, when light istransmitted from the exposed end of the one fiber of a correspondingpair to the at least partially reflective object, a portion of thetransmitted light that is passed through and is further transmitted fromthe at least partially reflective object in a different direction thanthe portion of the transmitted light that is reflected by the at leastpartially reflective object, each of the plurality of sensors receivingthe portion of the transmitted light from a different fiber of theplurality of pairs of optical fibers.